CBSE NCERT Solutions Chapter 5 Arithmetic Progressions Exercise 5.2 Question 8
8. An AP consists of 50 terms of which 3rd term is 12 and the last term is 106. Find the 29th term.
Solution:
An AP consists of 50 terms and the 50th term is equal to 106.
It is also given that
. {
is the 3rd term of AP}
Using formula
, to find nth term of arithmetic progression, we get
And
And
And
These are equations consisting of two variables. Lets solve them using substitution method.
Using equation
, we get
Putting value of
in the equation
, we get
Putting value of
in the equation,
, we get
Therefore, First term
and Common difference
To find 29th term, we use formula
which is used to find nth term of arithmetic progression, we get
Therefore, 29th term of AP is equal to
.
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